Pros
Passionate, smart, talented employees. Deep focus on all things related to biking, walking means you quickly become an expert in this ever-growing field. Great place to learn how to market, develop leads, win work, write proposals. Alta is the oldest bike-ped planning & design firm in the US. Principals are approachable, and a vast font of knowledge. Offices all over the country with relocation or establishing a satellite office possible.
Cons
High staff turnover at all levels below principal. Management skills vary depending on which office you're in. (If you're considering a job, talk with someone who has worked in the specific office that is hiring.) Sink or swim environment. Mid to senior level positions work about 50 hours/week. Specialist positions that support many projects can work more than that, depending on deadlines.